This invention relates to a drag reducing cooling system for a vehicle, and more particularly, for a streamlined vehicle with an engine forwardly disposed of a passenger compartment.
When a vehicle is provided with an engine at the front end, it is common practice to position a radiator also at the front end. The vehicle body is formed with an opening at the front end so that when the vehicle is moving forwardly, air will be rammed or directed into the front end opening to provide a source of air to cool the fluid in the radiator. The radiator, as known in the art, is designed as a heat exchanger to transfer heat from the radiator to the air so that fluid within the radiator will be cooled for recirculation through the engine.
When the vehicle is moving forward the vehicle body passes through an air space to define a plurality of air streams passing over the vehicle body. If the air stream paths follow a frequently changing direction the air stream experiences a change in momentum. Pressure forces acting on the vehicle body due to the plurality of air streams passing over it create drag which opposes vehicle movement through the air space. One vehicle structure which significantly changes the direction of the air stream is a forwardly facing opening or louvre used on a vehicle to ram or ingest air to a cooling system.
The vehicle body design which generates the least amount of drag is highly desirable and includes a streamlined forebody. A limiting factor in designing a low drag vehicle body is the forward facing cooling intake opening of the conventional cooling system at the front end of the vehicle. In addition, the frontal location of a conventional radiator is a prerequisite to the use of conventional ram cooling and therefore causes a severe limitation on the shape needed for low drag.
The prior art for front engine vehicles is illustrated by U.S. Pat. No. 4,226,217 (Haslbech, et al) issued Oct. 7, 1980, U.S. Pat. No. 4,081,050 (Hennessey, et al) issued Mar. 28, 1978, and U.S. Pat. No. 1,920,883 (Perkins) issued Aug. 1, 1933. These patents illustrate the previously acknowledged practice of providing forwardly facing openings or side plates extending outwardly from the body to ram or ingest air for the cooling system as the vehicle moves forward.
The present invention provides a solution to the above problems so that the radiator can be positioned adjacent or be a part of the vehicle engine at the front end while at the same time enabling the vehicle body to be designed with non-ram low drag characteristics. The invention provides a means for cooling the engine which does not utilize ram air, that is, no component of the cooling system receives cooling air resulting from the motion of the vehicle. The invention comprises a cooling system for a vehicle with an engine forwardly disposed and mounted in a streamlined body with a top portion extending over the engine and a pair of side portions extending substantially vertically downward. The cooling system includes a heat exchanger assembly and an air passage communicating therewith for transferring heat from the engine to air communicated through the air passage. The top portion and the pair of side portions form boundaries for a plurality of air streams which pass over and around the body when the vehicle is moving. In addition the air passage leads to an opening or openings on the body, and the openings cooperating with the side portions to substantially define uninterrupted air streams across the openings.
It is an advantage of the present invention that the portion of the vehicle body with a forwardly facing component can be a smooth uninterrupted streamlined shape so that air drag developed by the vehicle is minimal. This result follows since the cooling air inlet openings lack a forwardly facing component or louvered projections to ram air to the radiator.
Many other objects, purposes and advantages of the invention will be clear from the following detailed description of the drawings of the preferred embodiment of the invention.